Stamping device



STAMPING DEVICE Filed July 26,

Patented Apr. 5, 1932 UNITEDA STATES PATENT OFFICE RICHARD M. DUGDALE, OF DEDHAM, MASSACHUSETTS, ASSIGNOB TO I'ABBINGTON MANUFACTURING COMPANY, I BOSTON, MASSACHUSETTS, A CORPORATION 0l' MASSACHUSETTS BTAMPIN G DEVICE application med July. as, mao. serial No. 470.898.

This invention relates to printing or stamping devices which'may for example be of the type illustrated and described 1n my copending a plication Serial No. 391,788 filed September 11, 1929, and Serialy Nos. 404,290 and 404,291 both filed November 2, 1929. Devices of this type are usefulV in rinting from detachable sheet metal print- 111g plates of the type used to identify customers in retail transactions, and the devices include as aneoperative element an ink ribbon which is pressed, together witha sheet to be printed, against the sheet metal printing plate to eiect printin Objects of the invention are to provide or advancing the ribbon to present fresh portions thereof to the printing ressure device without danger of breaking t e ribbon and without danger of smearing the printed sheet.

The present invention is articularly useful in devices such as descri d in the above copending applications wherein mechanism for advancing the ribbon is o erated by movement of the mechanism whic causes the my invention.

For thelpurposes of illustration and by way of exam e my invention will be explained with re erence to one specific 'A embodiment wherein it is utilized in a device of the claimed in my copending applications referred to above.

In the drawings:

Fi 1 is a side elevation of a stamping or printing device, the view being taken from the side of the device opposite to that at which the operator usually stands, and a por.

tion of the side wall of the device being p broken away;

printing pressure to be applied to the ribbon.,

Fig 2 is a fragmentary view similarto Fig. 1, showing certain parts of the device 1n operation; l I" Fig. 3 is a section on theline 3-3 of Fig. 4 is a section on the line 4-4 of Fig. 1 with the ribbon reels' and'certain other parts removed; and

Fig. 5 is a fragmentary side elevation of a portion of the device, this view being taken 1n a dlrection opposite to that of Flg. 1.

The illustrated embodiment of my mventlon includes numerous parts similar to or identical with corresponding parts in the device illustrated and claimed in my co nding application Serial No. 404,291 filed ovember 2, 1929, which may be referred to for a fuller description of these parts. The i1- lustrated device, which is adapted particularly for printing customers names and addresses upon sales sli s in connection with retail transactions, inc udes a base 11, a plate holder, indicated generally by the reference character 12, rigid with the base and aced therefrom by a block 13, a casing 14 hlnged to the plate holder. and base. at 15 and containing pressure-applying mechanism and ,ribbon-feeding and reversing mechanism,

and an operating handle 16 for swinging the casing and contained mechanism toward and from the plate holder 12 and for operating the pressure applying mechanism and ribbon feeding and reversing mechanism. A suitable printing plate 18, which is preferably of the type illustrated and claimed in my copending application Serial No. 374,715 filed June 29, 1929, comprising a sheet of ductile metal having a struck-up central rtion which carries characters 19, ig. 2) may be detacha ly retained by' the plate holder 12. The type characters 19 of'thisplate are preferably raised characters disposed in direct order so that a sheet of paper to be printed may be laid directly upon the printing plate and receive upon its upper face as a Y ing operation. An ink ribbon 29 is contained within the l 14 and overlies a sheet of thus upon the printing plate. suitab e pressure applying member,

rinted indicia,` t of the printwhich may be any kind of a platen, but which is herein shown as a pressure roller 28 having hub members 39 movably retained within slots 40 of a channel shaped guide member 43, is adapted to be moved across a printing plate retained by the holder and in so doing to press the inked ribbon 29 and one or more sheets of paper against the plate. Suitable mechanism for moving the pressure roller 28 preferably comprises a. vertical plunger 30 connected by a pin and slot connection to the operating handle 16 and movable downwardly against the action of a coil spring 31. The plunger 30 carries a cam' surface 32 at its lower end which operatively engages a cam follower 33 (Fig. 5) mounted upon a bifurcated bracket 36 which is pivotally mounted at 36a to a sleeve 81 fast to the casing 14. The bifurcated bracket 36 engages at its lower end opposite ends of the pressure roller 28. In this manner pressing down on the operating handle 16 depresses the plunger 3() and causes the cam surface 32 to swing the cam follower 33 and the bracket 36 to the right in Fig. 1, thus carr ing the pressure roller 28 to the right across t e printing plate. Releasing the operating handle 16 enables the spring 31 to raise the plunger 3() to its initial position, while a coil spring 35 serves to return the bifurcated bracket 36 and the pressure roll 28 to their positions at the left-hand side of the casing in Fig. 1. It will readily be understood that the exact structure of the parts thus far described is not essential to my invention, as numerous other pressure-applying devices and operating mechanisms therefor might be employed to press an inked ribbon a ainst a sheet of paper and against the printing plate 18. At this point it should be noted however that the pressure-applying mechanism is preferably capable of applying a considerable pressure to the inked ribbon 29 and the sheet or sheets of paper being printed, in order to obtain clear, legible impressions, preferably on a number of superposed sheets with interposed carbon sheets.

The device preferably includes in addition to the outer casing 14, an inner casing 44 which may be fastened to the wall of the outer casing (Fig. 4) and which preferably comprises spaced vertical side portions 42 to which the channel -shaped guide 43 is preferably fastened.

The inked ribbon 29 is wound upon ribbon reels 40 and 41 rotatably mounted upon shafts 52 and 53 which are retained in the casing 14 by means ofscrews 62, (Fig. 4) and which have enlargements in the form of anges 63 spaced from the back of the outer casing 14 adapted loosely to receive a ratchet wheel 50 or 51 and a spacing washer 64. Each ratchet wheel has pins projecting forwardly therefrom immediately outside the periphery of the flange 63 f the shafts 52 and 53 and adapted operatively to engage struck-up ears 66 on the ribbon reel, thus to rotate the reel. As shown in Figs. 1 and 4, a spring 70 is mounted on the inner casing 44 beneath each ribbon reel by means' of struck-'up ears 67 and bears against the spacing washer 64. This arrangement of parts is such that either of the reels 40 or n41 may be rotated by force applied to the ratchet teeth of the associated ratchet, but is such that rotation of either of the wheels is resisted by the frictional engagement of the spring with the spacing washer 64. As shown in Fig. 1 the ratchet wheels have their teeth reversed with respect to each other so that the ink ribbon 29 is wound in one direction when one of the ratchet wheels is rotated and in the opposite direction when the opposite ratchet wheel is rotated.

The device' is preferably provided with mechanism for Winding up the ribbon upon one of these reels upon movement of the actuating plunger 30. Referring to Fig. 1, a tumbler 46 is pivotally mounted on the lower end of the plunger 30 between the two ribbon reels to swing toward either of these reels. Tumbler 46 is provided on one face with a pair` of countersunk holes 47 and 48 on opposite sides of its center, and plunger 30 carries a. spring-pressed pin 49 adapted to project into either of these holes and thereby yieldingly to position the tumbler adjacent to one or the other of these rolls of inked ribbon. Tn the position of Fig. 1, pin 49 is shown as engaging hole 47. Tumbler 46 is provided with two pivotally mounted pawls 58 and 59 for engaging respectively ratchet wheels 50 and 51. As the tumbler 46 returns to its uppermost position Aat the end of the printing operation, one of the pawls 58 or 59, depending upon the position of the tumbler, engages the adjacent ratchet wheel and winds a portion of the ribbon upon the corresponding reel. In this manner the ribbon is advanced in a step by step manner while the ratchet wheels are prevented from moving unduly by means of the frictional engagement of the springs 70 with the spacing washers 64. The tumbler 46 is preferably provided at its opposite sides, adjacent the respective rolls of ribbon, with ribbon-contacting,members 55 and 56. As the amount of ribbon on a reel increases to a certain extent the ribbon wound on the reel will force this ribbon-contacting member away from the aXis of the reel, thus swinging the tumbler 46 to its opposite position and effecting a reversal of feeding direction of the ribbon.

From the above description of a preferable form of pressure-applying mechanism and a preferable form of ribbon-feeding mechanism, it will appear that with these mechanisms thus operating in conjunction there is, unless some precautionary measures are observed, danger that the device will be so opneuem erated that the ribbonmechanism ter is subjected to the compression .of the` pressure roll, or else advance the ribbon while the latter is being pressed against the printed sheet and thereby produce a smear upon the upper surface of the sheet. l

For the urpose of protecting the device against suc undesired operations, provision is made for regulating the tension o the portion of ribbon intermediate the winding reel and the pressure roll, the regulation of tension preferably being obtained by' a controlled shortening of the path of ribbon between these two instrumentalities so that winding may' take lace without simultaneous movement of the ribbon under the pressure roll. As illustrative of preferred means for accomplishing this end, the laccompanying drawings show a pair of springs 80, having'cut-out portions 80l (Fig. 3) to increase their resiliency, and fastened to opposite ends of the channel-shaped guide 43. These springs 80 extend generally in prolongation of the side,

xible or yielding guide members for the ribbon intermediate the ribbon reels and the fixed guides comprising the side portions 42 of the inner casing. Referring to Fig. 1, the inked ribbon 29 passes from one ribbon reel to the other in an indirect path, portions of which are determined by the flexible or yielding guide members 80 which are so dispod that they define projecting angles of the ribbon path. Preferably the springs are rounded at their outer ends, as shown in Figs. 1 and 2, to facilitate the passage of the ribbon. The arrangement of these springs 80 at projecting angles of the path of the ribbon is such that undue tension upon the ribbon as set up by simultaneous winding of a ribbon reel and compression of a ribbon by the pressure roll, causes the adjacent spring 80 to yield and thereby shorten to some extent the path of the ribbon and relieve the tension thereof,

portions 42 of the inner-'casing and constitute thus preventing breaking or preventing the ribbon 29 from being pulled from under the pressure roll with a. consequent smearing of the printed sheet. Fig. 2 illustrates diagrammatically this mode of operation, and referring `to this figure it will be noted that the ressure roll moving (on its return stroke) 1n tbe direction of the arrow M, has not yet left the region of the raised type characters 19 of the printing plate but is still compressing the inked ribbon therebetween. At this stage the tumbler 46` through its pawl 58, has already engaged the ratchet wheel of the reel 40 and has wound a certain amount of ribbon thereon, the increased tension thus set up in the ribbon having caused the adjacent spring to move slightly in a direction which tends to shorten the path of the ribbon.

Further movement of the rassure roll'28 in the direction of the arrow in Fig. 2 so that thcrollleavesthe region oftheraisedtype characters 19 and thus ceases to prem hard upon the inked ribbon 29, will relieve the excess tension in the ribbon, thereby enab the ilexed spring 80 to return to its initi v ertical ositio n of Fig. 1. This outward motion of t e spring 80, which referably takes place while the ratchet whee is still e y the pawl of the tumbler, o rates to draw ribbon from the reel 41 past t e guide 42 and under the roll 28. Such movement of the ribbon under the influence of the spring 80 is unaccompamed by any r of b or smearing since the roll 28 as at this point ceased to appl ressure to the ribbon. The sprmg. 80 in a tion to serving as a tension regulatmg member may therefore also be rearded as a device effective to receive ene m the initial actuation of the associaltegiyi ratchet wheel, and effective later to advance the ribbon underneath the pressure roll when the pressure applied by the pressure roll has gunnllinshedftcluchba extent that .danger of re age o e ri n or smea sheet is passed. mg of the clAaim:

stam ing device com rising' a late holder for iitachably a priiiting plate, an ink ribbon adapted to overlie a sheet' of paper when the latter is placed in printing position upon a printing plate rctained by the plate holder, a pressure roll moyable over the'portioii of the ink ribbon which o verlies the printing late, operating mechanism for thus moving the roll, rotatable ribbon reels adapted to wind u and unwind the ribbon, reel-rotating m operable by said operating mechanism to rotate one of said reels during movement of the pressure roll, and a yieldable member vde- {in mg a portion of the path of said ribbon, said member, through yielding, permi an end portion of the ribbon to be woun up without simultaneous advance of the portion of ribbon engaged by the premura roll, subsequent return of the'yieldable member serving to advance the remainder of the ribboA.

2. stamping device com rising a casing an ribbon and rotatablle; reels thereforz within the casing, a pressure roll adapted to press the ribbon toward a printin plate, a guide for the roll extending across t e casing, guides detinmg generally vertical paths for the ribbon leading to and from a horizontal plane traversed by the roll, and spring abutments defining rojecting angles in the path of the ribbon adjacent the reels, where upon tensioning of the ribbon by rotation o a reel the adjacent abutment yields to permit straightening and winding up of a portion of the ribbon without corresponding aimu1- taneous progression of the portion of the ribbon engaged by the roll.

3. In a stamping device, a horizontal guide lll for a pressure roll, a vertical ribbon guide at each end of the horizontal guide for guiding an ink ribbon to a horizontal plane adjacent the bottom of the horizontal guide, and approximately vertically disposed sprin at each end of the horizontal guide de ing paths for the ribbon as the latter a proaches and leaves the vertical ribbon ies.

Signed by me at Boston, assachusetts,- lo this 15th day of July, 1930.

,. RICHARD M. DUGDALE. 

